The Metropolitan Opera, which has continued to struggle at the box office and face what it calls “economic challenges,” has offered voluntary buyouts to 21 of its 243 administrative employees, the company said on Thursday.

“As you know, the Met continues to face economic challenges as it copes with the changing environment for presenting opera,” Peter Gelb, the Met’s general manager, said in a note he sent to the entire company on Thursday, a few days after the season opened. “As part of our ongoing efforts to reduce costs, we have offered 21 members of the administrative staff the possibility of participating in a voluntary retirement program, which includes supplemental financial benefits.”

The Met, the nation’s largest performing arts organization, has been working to cut its costs for several years. According to its most recent tax returns, the company spent $294.3 million in the fiscal year ending in July 2016 — its lowest operating budget in seven years — but still ran a small deficit of $177,000. And it has struggled to sell tickets recently: Last season the Met reported that it had taken in just 67 percent of its potential box-office revenue, which was only a slight improvement from the prior season, when it recorded its worst showing ever.

Citing its need to save money, the company took the rare step this season of canceling a previously announced new production of Verdi’s “La Forza del Destino” by the daring director Calixto Bieito. The Met is seeking to cut its budget this year to $280 million, officials said. A small portion of the necessary cuts are to come from administrative costs; officials said that the Met hopes to achieve those savings through voluntary buyouts.

The administrative employees being offered early retirement are not members of the Met’s powerful unions, which represent its orchestra, chorus, stagehands and others. In 2014 the Met won concessions from its unions after bitter negotiations that brought the company to the brink of a lockout; it also eliminated 22 nonunion positions, mostly through layoffs. But some of the pay cuts agreed to in that contract, which reached 7 percent, are to be partially restored with raises of up to 3 percent in the second half of this year, as several important contracts near their end. (The contracts with several major unions, including the ones representing the Met’s orchestra and chorus, expire at the end of July.)

In his note to the staff, Mr. Gelb wrote that “I appreciate your concerns and hope for your understanding that we are looking out for the long term fiscal health of our beloved institution.”